Monoethanolamine

Structural formula
General
Surname	Monoethanolamine
other names	2-aminoethan-1-ol ( IUPAC ); Ethanolamine (simplified); Aminoethanol; Colamin; Olamine ( INN ); beta-hydroxyethylamine;
Molecular formula	C 2 H 7 NO
Brief description	colorless, oily liquid with an ammonia- like odor
External identifiers / databases
EC number	205-483-3
ECHA InfoCard	100,004,986
PubChem	700
ChemSpider	13835336
DrugBank	DB03994
Wikidata	Q410387
properties
Molar mass	61.08 g mol −1
Physical state	liquid
density	1.02 g cm −3 (20 ° C)
Melting point	10 ° C
boiling point	172 ° C
Vapor pressure	0.5 h Pa (20 ° C); 1.63 hPa (40 ° C); 3.43 hPa (50 ° C);
pK s value	9.50
solubility	miscible with water; miscible with alcohols;
Refractive index	1.4541 (20 ° C)
safety instructions
H and P phrases	H: 302-312-332-314-335-412
	P: 261-273-301 + 312 + 330-303 + 361 + 353-304 + 340 + 310-305 + 351 + 338
MAK	DFG : 0.2 ml m −3 , 0.51 mg m −3 ; Switzerland: 2 ml m −3 or 5 mg m −3 ;
Toxicological data	1720 mg kg −1 ( LD 50 , rat , oral ) ; 1010 mg kg −1 ( LD 50 , rabbit , transdermal ) ;
	As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions . Refractive index: Na-D line , 20 ° C

Monoethanolamine (according to IUPAC nomenclature: 2-aminoethan-1-ol , also referred to as MEA for short ) is an organic-chemical compound from the group of amino alcohols . It is their simplest representative and is used as a raw material in the chemical industry .

Occurrence

Monoethanolamine is the biogenic amine of the amino acid serine . Ethanolamines occur as a polar head group in phosphatidylethanolamine , which belongs to the group of phospholipids . Phospholipids essentially form the lipid bilayer in cell membranes . This polar head group can also be found in endocannabinoids .

Extraction and presentation

Monoethanolamine is produced on an industrial scale by reacting ethylene oxide with ammonia at temperatures of 60-130 ° C. and pressures of 70-160 bar in the presence of water and an acidic catalyst . Acidic zeolites (for example aluminosilicates ) or organic ion exchange resins in the H form (protons) are particularly preferably used.

The higher ethanolamines, especially diethanolamine and triethanolamine, are produced as by-products . The proportion of monoethanolamine can be greatly increased by an excess of ammonia. The molar ratio of ammonia to ethylene oxide is therefore preferably 20: 7. The complete reaction preferably takes place in stirred tank or tubular reactors. The reaction mixture is purified and worked up by multi-stage distillation in rectification columns .

properties

Physical Properties

Monoethanolamine has a relative gas density of 2.11 (density ratio to dry air at the same temperature and pressure ) and a relative density of the vapor-air mixture of 1.00 (density ratio to dry air at 20 ° C and normal pressure ). In addition, ethanolamine has a vapor pressure of 0.50 hPa at 20 ° C, 1.63 hPa at 40 ° C and 3.43 hPa at 50 ° C.

Chemical properties

Monoethanolamine is a difficult to ignite liquid from the group of amino alcohols . It can be mixed with water and many alcohols . Furthermore, ethanolamine is hygroscopic and absorbs water vapor and carbon dioxide . The liquid is difficult or very difficult to volatilize. The substance can polymerize on contact with acrolein or acrylic acid . In addition, monoethanolamine reacts strongly with oxidizing agents and acids as well as iron- sulfur compounds . An aqueous solution of concentration 100 g / l at 20 ° C has a pH of 12.1. As a result, solutions of monoethanolamine are strongly alkaline .

use

Monoethanolamine is used:

as a substitute for caustic soda in oven cleaners
as an additive in cooling lubricant
in the pulp industry as an organic solvent
in the dye industry
as a grinding aid for cement
as an additive in cleaning agents and cosmetics (fatty acid derivative for detergents )
as an absorbent for carbon dioxide and hydrogen sulfide in amine scrubbing such as in the direct air capture process or in nuclear submarines
as an intermediate in the manufacture of surfactants
in medicine
Production of the salt ethanolamine · HF, a hydrofluoride . This patented amine fluoride was previously marketed as an active ingredient in a toothpaste under the trade name Biox Fluor ^® by Knoll AG, Ludwigshafen.
as an intermediate for the production of other chemical compounds such as 2-mercaptothiazole , phenylethanolamine and ethylenediamine .

safety instructions

Monoethanolamine is a difficult to ignite liquid . The vapors can form explosive mixtures with air when the substance is heated above its flash point . The substance is mainly absorbed through the respiratory tract and skin . This can range from slight irritation to severe burns of the mucous membranes and skin. Furthermore, a skin-sensitizing effect was found. Chronic consequences can be skin changes . The ignition temperature is 410 ° C. The substance therefore falls into temperature class T2 and explosion group IIA. With a flash point of 85 ° C, monoethanolamine is considered to be relatively flame-retardant.

Risk assessment

Monoethanolamine was included by the EU in 2012 in accordance with Regulation (EC) No. 1907/2006 (REACH) in the context of substance evaluation in the Community's ongoing action plan ( CoRAP ). The effects of the substance on human health and the environment are re-evaluated and, if necessary, follow-up measures are initiated. The reasons for the uptake of monoethanolamine were concerns about high (aggregated) tonnage and widespread use, as well as the possible risk of sensitizing properties. The re-evaluation started in 2014 and was carried out by the United Kingdom . A final report was then published.

Individual evidence

↑ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j ^k ^l ^m ⁿ ^o ^p ^q Entry on 2-aminoethanol in the GESTIS substance database of the IFA , accessed on March 3, 2019 (JavaScript required)
^ Hall, HK, J. Am. Chem. Soc. , 1957 , 79 , 5441.
↑ ^a ^b entry on aminoethanols. In: Römpp Online . Georg Thieme Verlag, accessed on March 3, 2019.
↑ Entry on 2-aminoethanol in the Hazardous Substances Data Bank , accessed on March 3, 2019.
↑ Entry on 2-aminoethanol in the Classification and Labeling Inventory of the European Chemicals Agency (ECHA), accessed on March 3, 2019. Manufacturers or distributors can expand the harmonized classification and labeling .
↑ Swiss Accident Insurance Fund (Suva): Limit values - current MAK and BAT values (search for 141-43-5 or 2-aminoethanol ), accessed on September 14, 2019.
↑ ^a ^b Patent EP1289927B1 : Process for the production of ethanolamines. Published on May 14, 2014 , applicant: BASF SE, inventor: Matthias Frauenkron, Ulrich Müller, Wolfgang Harder, Jörg Unger, Johann-Peter Melder, Anton Meier, Walter Himmel. ‌
↑ Patent DE971375 : Process for the production of an alkaline, soap-free, reactive fluorine in addition to calcium carbonate containing toothpaste. Registered on August 26, 1951 , published on January 15, 1959 , applicant: Knoll AG , inventor: Oskar Eichler , Kurt Kraft, Philipp Zut. ‌
↑ German Dental Journal, Vol. 7, pp. 702 & 708 (1952)
↑ Klaus Weissermel , Hans-Jürgen Arpe , Charlet R. Lindley, Stephen Hawkins: Chap. 7. Oxidation Products of Ethylene . In: Industrial Organic Chemistry . Wiley-VCH , 2003, ISBN 3-527-30578-5 , pp. 159-161.
^ European Chemicals Agency (ECHA): Substance Evaluation Report and Conclusion Document .
↑ Community rolling action plan ( CoRAP ) of the European Chemicals Agency (ECHA): 2-aminoethanol , accessed on March 26, 2019.

[GESTIS-1] ↑ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j ^k ^l ^m ⁿ ^o ^p ^q Entry on 2-aminoethanol in the GESTIS substance database of the IFA , accessed on March 3, 2019 (JavaScript required)

[2] Hall, HK, J. Am. Chem. Soc. , 1957 , 79 , 5441.

[RÖMPP-3] try on aminoethanols. In: Römpp Online . Georg Thieme Verlag, accessed on March 3, 2019.

[HSDB-4] Entry on 2-aminoethanol in the Hazardous Substances Data Bank , accessed on March 3, 2019.

[CLP_100.004.986-5] Entry on 2-aminoethanol in the Classification and Labeling Inventory of the European Chemicals Agency (ECHA), accessed on March 3, 2019. Manufacturers or distributors can expand the harmonized classification and labeling .

[6] Swiss Accident Insurance Fund (Suva): Limit values - current MAK and BAT values (search for 141-43-5 or 2-aminoethanol ), accessed on September 14, 2019.

[VERFAHREN-7] Patent EP1289927B1 : Process for the production of ethanolamines. Published on May 14, 2014 , applicant: BASF SE, inventor: Matthias Frauenkron, Ulrich Müller, Wolfgang Harder, Jörg Unger, Johann-Peter Melder, Anton Meier, Walter Himmel. ‌

[8] Patent DE971375 : Process for the production of an alkaline, soap-free, reactive fluorine in addition to calcium carbonate containing toothpaste. Registered on August 26, 1951 , published on January 15, 1959 , applicant: Knoll AG , inventor: Oskar Eichler , Kurt Kraft, Philipp Zut. ‌

[9] German Dental Journal, Vol. 7, pp. 702 & 708 (1952)

[weissermel-10] Klaus Weissermel , Hans-Jürgen Arpe , Charlet R. Lindley, Stephen Hawkins: Chap. 7. Oxidation Products of Ethylene . In: Industrial Organic Chemistry . Wiley-VCH , 2003, ISBN 3-527-30578-5 , pp. 159-161.

[11] European Chemicals Agency (ECHA): Substance Evaluation Report and Conclusion Document .

[12] Community rolling action plan ( CoRAP ) of the European Chemicals Agency (ECHA): 2-aminoethanol , accessed on March 26, 2019.